[PATCH] tests: add test_response_start_auth_session_no_sessions_2

[Jarkko Sakkinen <jarkko@kernel.org>]

Add a test taken from tpm2sh trace output, which reveals a bug in the
response parser not catched by previous tests.

Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
---
This is a embarrassing critical bug and damage from refactorization
where `tpm_response!` macro was removed which was a compilicated task.
The bright side is that the quality of test suite also leveled up
as consequence and missing something as critical as this will become
factors more difficult.

Luckily response parsing it not too complicated, and this can be fixed
quite easily. Dispatcher must be internally updated to pass the runtime
parsed tag forward (just like it does for cc). I.e. a few macro updates
should do.

I should have a fix for this very soon!
 tests/runner.rs | 23 ++++++++++++++++++++++-
 1 file changed, 22 insertions(+), 1 deletion(-)

diff --git a/tests/runner.rs b/tests/runner.rs
index b63c801..3d2a1dc 100644
--- a/tests/runner.rs
+++ b/tests/runner.rs
@@ -26,7 +26,7 @@ use tpm2_protocol::{
         TpmCreatePrimaryCommand, TpmEvictControlCommand, TpmFlushContextCommand,
         TpmFlushContextResponse, TpmGetCapabilityCommand, TpmHashCommand, TpmNvWriteCommand,
         TpmPcrEventResponse, TpmPcrReadCommand, TpmPcrReadResponse, TpmPolicyGetDigestResponse,
-        TpmStartAuthSessionCommand, TpmStartAuthSessionResponse,
+        TpmResponseBody, TpmStartAuthSessionCommand, TpmStartAuthSessionResponse,
     },
     TpmBuffer, TpmBuild, TpmErrorKind, TpmParse, TpmPersistent, TpmSession, TpmSized, TpmWriter,
     TPM_MAX_COMMAND_SIZE,
@@ -947,6 +947,26 @@ fn test_response_start_auth_session_no_sessions() {
     assert_eq!(resp, original_resp);
 }
 
+fn test_response_start_auth_session_no_sessions_2() {
+    let response_hex = "8001000000300000000002000000002000647915de6106c955b26456b8b8a3b10546fa446405d4eb2e1fb0247fb52080";
+    let response_bytes = hex_to_bytes(response_hex).unwrap();
+    let (rc, body, sessions) = tpm_parse_response(TpmCc::StartAuthSession, &response_bytes)
+        .unwrap()
+        .unwrap();
+    let mut built_bytes = [0; TPM_MAX_COMMAND_SIZE];
+    let len = {
+        let mut writer = TpmWriter::new(&mut built_bytes);
+        match body {
+            TpmResponseBody::StartAuthSession(ref resp_struct) => {
+                tpm_build_response(resp_struct, &sessions, rc, &mut writer).unwrap();
+            }
+            _ => panic!("Parsed the wrong response type!"),
+        }
+        writer.len()
+    };
+    assert_eq!(&built_bytes[..len], &response_bytes);
+}
+
 fn test_tpm2b_build_length_too_large() {
     let large_slice: &[u8] = unsafe {
         std::slice::from_raw_parts(
@@ -1156,6 +1176,7 @@ test_suite!(
     test_response_parse_policy_get_digest,
     test_response_start_auth_session,
     test_response_start_auth_session_no_sessions,
+    test_response_start_auth_session_no_sessions_2,
     test_tpm2b_build_length_too_large,
     test_tpmbuffer_try_from_slice_too_large,
     test_tpm_rc_base_from_raw,
-- 
2.39.5